Particle size breakup device and its performance estimation method and scale up method

ABSTRACT

Herein is disclosed a comprehensive mixer performance estimation method that can be applied to the mixers of the rotor-stator type having various configurations and circulation systems. 
     Specifically, the performance estimation method for the mixers of the rotor-stator type includes the steps of: obtaining the homogenization index: H.I. for each of the mixers, measuring the size of each of the mixers, the power requirements and flow rates during the running time of each of the mixers, estimating the magnitude (smallness or greatness) of the configuration dependent term value of each of the mixer as a whole which is specific to each of the mixers, and estimating the performance of each of mixers accordingly.

BACKGROUND

1. Technical Field

Generally, the present invention relates to mixers, and morespecifically to a mixer of the so-called rotator-stator type thatincludes a stator having a plurality of openings or holes and a rotorthat is disposed on the inner side of the stator and spaced by aparticular gap away from the stator.

2. Background

As shown in FIG. 1, it is general that the mixer of the so-calledrotor-stator type generally comprises a mixer unit 4 that includes astator 2 having a plurality of openings (holes) 1 and a rotor 3 disposedon the inner side of the stator 2 and spaced by a particular gap 6 fromthe stator 2. Such mixer of the rotor-stator type is provided forsubjecting a fluid being processed to the emulsification, dispersion,particle size breakup, mixing or any other similar process, by takingadvantage of the fact that a high shear stress may be produced in theneighborhood of a gap between the stator 3 rotating at high-speeds andthe fixed stator 2. This mixer is used for mixing or preparing the fluidbeing processed, and has a wide variety of applications in which foods,pharmaceutical medicines, chemical products and others can bemanufactured.

The mixer of the rotor-stator type may be classed according to the typeof the circulation mode for the fluid being processed, that is, onebeing the externally circulated mixer in which the fluid liquid beingprocessed may be circulated in the direction indicated by the arrow 5 ain FIG. 2, and the other being the internally circulated mixer in whicha liquid being processed may be circulated in the direction indicated bythe arrow 5 b in FIG. 2.

For the mixers of the rotor-stator type, many different configurationsand circulation modes or systems have been proposed. For example, thereis the Japanese patent application No. 2006-506174 in which the mixer ofthe rotor-stator type and the particle size breakup method are proposed,in which the mixer includes a stator having a plurality of openings(holes) and a rotor disposed on the inner side of the stator and spacedby a specific gap away from the stator. It is disclosed that the mixermay be used widely in the fields in the pharmaceutical medicines,nutrition supplement foods, other foods, chemical products, cosmeticsand the like can be manufactured. It is also disclosed that the methoddisclosed enables the scale up function to be performed in theefficient, simple and easy manner.

In addition, for those past years, several indices (theories) have beenreported as the performance estimation method for the mixers having thedifferent configurations.

Not only for the mixer of the rotor-stator type as described above butalso for all other type mixers, it is reported that, when theliquid-liquid dispersion operation in particular occurs, for example,the drop diameter size can be discussed in terms of the magnitude(smallness or greatness) of the values that can be obtained bycalculating the average energy dissipation rate (Publications 1 and 2).In those publications 1 and 2, however, the method for calculating theaverage energy dissipation rates is not disclosed specifically.

The publications 3 to 6 report several study cases that may be appliedto each individual mixer and in which the results obtained by therespective experiments have been organized into the tabular forms. Inthose study cases (Publications 3 to 6), however, it is considered thatthe mixer's particle size breakup function is only affected by the gapbetween the rotor and stator and by the openings (holes) on the stator.Only the information that is different for each different type mixer isreported.

Several study cases are reported (Publications 7 and 8), in which theparticle size breakup mechanism for the mixer of the rotor-stator typewas considered and discussed. In those publications 7 and 8, it issuggested that the energy dissipation rates of the turbulent flow willcontribute to the particle size breakup effect, and the particle sizebreakup effect may be affected by the frequency (shear frequency) of theturbulent flow with which the particle size breakup effect is placedunder the shear stress of the fluid being processed.

For the scale-up method for the mixer of the rotor-stator type, thereare several reports (Publication 8) in which the final drop diameter(maximum stable drop diameter) can be obtained during the long-timemixer running period. This, however, is not practical in the actualproduction sites and is of no utility. Specifically, there are noreports regarding the study cases in which the processing (agitation andmixing) time of the mixer is the object for consideration, and thosestudy cases are not useful enough to estimate the drop diameters thatcan be obtained during the particular mixer running period. Although itis reported that the drop diameters may be estimated by considering themixer processing time, yet only the phenomenon (factual action) that isbased on the actual measured values (experimental values) is reported.There are no study cases in which such phenomenon is analyzedtheoretically.

The following publication, which is the document related to the patentapplication, is cited herein for reference:

-   Japanese Patent Application No. 2005-506174

The following publications, which are not related to the patentapplication, are cited herein for reference:

-   (1) David, J. T.; “Drop Sizes of Emulsions Related to Turbulent    Energy Dissipation Rates”, Chem. Eng. Sci., 40, 839-842 (1985) and    David J. T.; “A Physical Interpretation of Drop Sizes in    Homogenizers;-   (2) Agitated Tanks, Including the Dispersion of Viscous Oils”, Chem.    Eng. Sci., 42, 1671-1676 (1987);-   (3) Calabrese, R. V., M. K. Francis, V. P. Mishra and S.    Phongikaroon; “Measurement and Analysis of Drop Size in Batch    Rotor-Stator Mixer”, Proc. 10th European Conference on Mixing, pp.    149-156, Delft, the Netherlands (2000);-   (4) Calabrese, R. V., M. K. Francis, V. P. Mishra, G. A. Padron    and S. Phongikaroon; “Fluid Dynamic and Emulsification in High Shear    Mixers”, Proc. 3rd World Congress on Emulsion, pp. 1-10, Lyon,    France (2002);-   (5) Maa, Y. F., and C. Hsu, and C. Hsu; “Liquid-Liquid    Emulsification by Rotor/Stator Homogenization”, J. Controlled.    Release, 38, 219-228 (1996);-   (6) Barailler, F., M. Heniche and P. A. Tanguy; “CFD Analysis of a    Rotor-Stator Mixer with Viscous Fluids”, Chem. Eng. Sci., 61,    2888-2894 (2006);-   (7) Utomo, A. T., M. Baker and A. W. Pacek; “Flow Pattern,    Periodicity and Energy Dissipation in a Batch Rotor-Stator Mixer”,    Chem. Eng. Res. Des., 86, 1397-1409 (2008);-   (8) Porcelli, J.; “The Science of Rotor-Stator Mixers”, Food    Process, 63, 60-66 (2002);-   (9) Urban, K.: “Rotor-Stator and Disc System for Emulsification    Processes”, Chem. Eng. Technol., 29, 24-31 (2006)

SUMMARY OF THE INVENTION

In the patent application cited above, the superiority (performance) ofthe particular mixer and the value range of the design on which themixer is based are disclosed, but the theoretical grounds on which thevalue range of the high-performance mixer design is based are notdescribed. The kinds and configurations of the high performance mixerare not described specifically.

It may be appreciated from the above description that, for those pastyears, several indices (theories) have been reported as the performanceestimation method for the mixers having the different configurations. Inmost cases, however, those indices can only be applied to the individualmixers having the same configuration. In the actual cases, however, theycannot be applied to the mixers of the various types having thedifferent configurations.

As noted above, there are almost no study cases in which the performanceestimation method and the scale-up method for those mixers of therotor-stator type have been defined. There are also no study cases inwhich those methods can be applied to the mixers of the various typeshaving the different configurations, and the data on the resultsobtained by the experiments on such study cases have not been organizedproperly and comprehensively.

For the performance estimation method and scale-up method for the mixersof the rotor-stator type according to the prior art, in most cases, thefinal drop diameters (maximum stable drop diameters) were obtained byusing the small scale device for each individual mixer and permittingthe device to run for the long time period, and were then estimated.More specifically, in the prior art, there is no estimation method thatcan be used to estimate the drop diameters that would be obtained byusing the large-scale devices (actual production installation) for themixers of the various types and permitting such large-scale devices torun during the particular time period, or there is no estimation methodthat can be used to estimate the particular drop diameters obtainedduring the particular running time or the processing or agitating timerequired until such particular drop diameters can be obtained.

For the above reasons, the performance estimation method and design(development and fabrication) method for the mixers were actuallyperformed on the trial and error basis by using the actually usedprocessing liquids.

It is, therefore, objects of the present invention to provide acomprehensive performance estimation method that is established so thatit can be applied to the mixers of the various types having the variousconfigurations that are likely to be affected mostly by the gap inparticular between the rotor and stator or the mixers of the varioustypes having the different circulation systems; to provide the designmethod that is established by taking the running conditions (processingtime) for such mixers into consideration; and to provide themanufacturing method (particle size breakup method) that is establishedto be used for manufacturing the foods, pharmaceutical medicines and thelike by using the above described performance estimation method anddesign method.

In a first aspect of the invention as defined in claim 1, it ischaracterized by the fact that the mixer of the rotor-stator typecomprises a mixer unit that includes a stator having a plurality ofopenings (holes) and a rotor that is disposed on the inner side of thestator and spaced by a particular gap away from the stator, wherein whena fluid being processed by the mixer is subjected to the emulsification,diffusion, particle size breakup, mixing or any other similar process,the Equation 1 below is calculated so that a particular drop diameterfor the fluid being processed by the mixer can be obtained during aparticular mixer running time, and the mixer is thus designed byestimating the particular mixer running time and the drop diameters thusobtained for the fluid being processed.

$\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$

In the Equation 1,

H.I Homogenization Index [m²/s³]ρ: Concentration [kg/m³]νh: Volume of the Gap [m³]

P_(h): Power Consumption [W]

Q: Flow Rate [m³/s]t_(m): Mixing Time [s]V: Fluid being Processed [m₃]

N_(p): Number of Powers [-] N_(qd): Number of Flow Rates [-] h: Heightof Stator [m] d: Diameter of Hole of Stator [m]

n_(s): Number of Holes of Stator [-]

l: Thickness of Stator [m]

σ: Gap between Rotor and Stator [m]

N: Number of Rotations [1/s]

C_(n): Configuration Dependent Term for Gap [m₅]

In a second aspect of the invention as defined in Claim 2, the mixer asdefined in Claim 1, it is characterized by the fact that the stator andthe rotor are arranged in such a manner that they can be moving closerto and or moving farther away from each other in the direction in whichthe rotary shaft of the rotor extends.

In a third aspect of the invention as defined in claim 3, the mixer asdefined in Claim 1 or Claim 2, it is characterized by the fact that themixer includes a plurality of stators each having a differentcircumferential diameter and a rotor disposed on the inner side of eachof the plurality of stators and spaced by a particular gap away fromeach of the stators.

In a fourth aspect of the invention as defined in Claim 4, the mixer asdefined in any Claims 1 to 3, it is characterized by the fact that thefluid being processed is introduced into the gap between the stators andthe rotor disposed on the inner side of each of the stators and spacedby the gap away from each of the stators.

In a fifth aspect of the invention as defined in Claim 5, the mixer asdefined in any Claims 1 to 4, it is characterized by the fact that therotor has a plurality of agitating blades extending radially from thecenter of rotation.

In a sixth aspect of the invention as defined in Claim 6, it ischaracterized by the fact that the method for estimating the performanceof the mixer of the rotor-stator type comprising a mixer unit thatincludes a stator having a plurality of openings (holes) and a rotordisposed on the inner side of the stator and spaced by a particular gapaway from the stator is provided, wherein the method for estimating theperformance of the mixer includes the steps of: using the Equation 1below to determine the homogenization index: H.I, measuring therespective sizes of the rotor and stator and the power requirements andflow rates during the mixer running time period which are included inthe Equation 1 below, and estimating the magnitude (smallness orgreatness) of the values of the configuration depending term in the gap,which are specific to each of the mixers of the different types.

$\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$

In the Equation 1,

H.I: Homogenization Index [m²/s³]ρ: Concentration [kg/m₃]νh: Volume of the Gap [m₃]

P_(h): Power Consumption [W]

Q: Flow Rate [m³/s]t_(m): Mixing Time [s]V: Fluid being Processed [m₃]

N_(p): Number of Powers [-] N_(qd): Number of Flow Rates [-] h: Heightof Stator [m] d: Diameter of Hole of Stator [m]

n_(s): Number of Holes of Stator [-]

l: Thickness of Stator [m]

σ: Gap between Rotor and Stator [m]

N: Number of Rotations [1/s]

C_(n): Configuration Dependent Term for Gap [m₅]

In a seventh aspect of the invention as defined in Claim 7, it ischaracterized by the fact that a method for scaling-up or scaling downthe mixer of the rotor-stator type comprising a mixer unit that includesa stator having a plurality of openings (holes) and a rotor disposed onthe inner side of the stator and spaced by a particular gap away fromthe stator is provided, wherein the method includes the steps of: usingthe Equation 1 below to calculate the values of the homogenizationindex: H.I on the experimental mixer installation and/or on the pilotplant mixer installation, and matching the values of the homogenizationindex: H.I. thus obtained against the values for the homogenizationindex: H.I. obtained on the actual mixer installation that isspecifically intended for scaling up or scaling down the mixer so thatthe former H.I. values can conform with the latter H.I. values.

$\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$

In the Equation 1,

H.I: Homogenization Index [m²/s³]ρ: Concentration [kg/m³]νh: Volume of the Gap [m³]

P_(h): Power Consumption [W]

Q: Flow Rate [m³/s]t_(m): Mixing Time [s]V: Fluid being Processed [m³]

N_(p): Number of Powers [-] N_(qd): Number of Flow Rates [-] h: Heightof Stator [m] d: Diameter of Hole of Stator [m]

n_(s): Number of Holes of Stator [-]

l: Thickness of Stator [m]

σ: Gap between Rotor and Stator [m]

N: Number of Rotations [1/s]

C_(n): Configuration Dependent Term for Gap [m₅]

In an eighth aspect of the invention as defined in Claim 8, it ischaracterized by the fact that foods, pharmaceutical medicines orchemical products are manufactured by subjecting the fluid beingprocessed to the emulsification, dispersion, particle size breakup,mixing or any other like process that occurs by using the mixer of therotor-stator type comprising the mixer unit that includes the statorseach having the plurality of openings (holes) and the rotor disposed onthe inner side of each of the stators and spaced by the particular gapaway from each of the stators, wherein the foods, pharmaceuticalmedicines or chemical products are manufactured by subjecting the fluidbeing processed to the emulsification, dispersion, drop breakup, mixingor any other like process by using the Equation 1 below and estimatingthe mixer running time and the drop diameters that are thus obtainedduring the mixer running time.

$\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$

In the Equation 1

H.I: Homogenization Index [m²/s³]ρ: Concentration [kg/m³]νh: Volume of the Gap [m₃]

P_(h): Power Consumption [W]

Q: Flow Rate [m³/s]t_(m): Mixing Time [s]V: Fluid being Processed [m₃]

N_(p): Number of Powers [-] N_(qd): Number of Flow Rates [-] h: Heightof Stator [m] d: Diameter of Hole of Stator [m]

n_(s): Number of Holes of Stator [-]

l: Thickness of Stator [m]

σ: Gap between Rotor and Stator [m]

N: Number of Rotations [1/s]

C_(n): Configuration Dependent Term for Gap [m₅]

In a ninth aspect of the invention as defined in Claim 9, it ischaracterized by the fact that the method for manufacturing foods,pharmaceutical medicines or chemical products by subjecting the fluidbeing processed to the emulsification, dispersion, particle sizebreakup, mixing or any other like process that occurs by using the mixerof the rotor-stator type comprising the mixer unit that includes thestator having the plurality of openings (holes) and the rotor disposedinside the stator and spaced by the particular gap away from the stator,wherein the method includes the steps of: using the Equation 1 below,estimating the mixer running time and the drop breakup diameters thusobtained by the calculating step during the mixer running time, andmanufacturing the foods, pharmaceutical medicines or chemical productsbased upon the estimating step.

$\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$

In the Equation 1,

H.I: Homogenization Index [m²/s₃]ρ: Concentration [kg/m₃]νh: Volume of the Gap [m₃]

P_(h): Power Consumption [W]

Q: Flow Rate [m³/s]t_(m): Mixing Time [s]V: Fluid being Processed [m₃]

N_(p): Number of Powers [-] N_(qd): Number of Flow Rates [-] h: Heightof Stator [m] d: Diameter of Hole of Stator [m]

n_(s): Number of Holes of Stator [-]

l: Thickness of Stator [m]

σ: Gap between Rotor and Stator [m]

N: Number of Rotations [1/s]

C_(n): Configuration Dependent Term for Gap [m₃]

In the present invention, the index that is called the homogenizationindex: H.I is utilized. The homogenization index that may be applied toeach of the mixers of the various types having the differentconfigurations and circulation systems that are offered from each of themanufacturers can be calculated separately from the geometrical sizes,running powers and flow rates that are specific to the rotor and stator.The homogenization index may be expressed by separating the values ofthe configuration dependent term from the values of the runningcondition dependent term, both of which terms are specific to the gapfor each individual mixer.

When the performance for each individual mixer is estimated by thevalues for the homogenization index: H.I., for example, when the mixerperformance is estimated by the particle size breakup trend, themagnitude (smallness or greatness) of the values for the configurationdependent term as measured in the mixer gap can be used.

When each individual mixer is to be scaled up or scaled down, themeasured values of the homogenization index: H.I., as coupled with thevalues of the configuration dependent term and running conditiondependent term that are specific to the mixer gap may be used, and eachindividual mixer can be designed by matching the values of H.I. againstthe respective values of the above terms so that the former H.I. valuecan conform with the latter term values.

Based upon the discoveries described above, the mixer that provides thehigher particle size breakup and emulsification efficiencies than any ofthe prior art mixers can be developed and designed as the highperformance mixer theoretically and experimentally.

In the present invention, specifically, the value range for the highperformance mixer can be specified in terms of the values of theconfiguration depending term (factor) in the mixer gap, and can beapplied to the performance estimation method for each individual mixer.In order to derive the values for the homogenization index: H.I., thepresent invention proposes the equation that allows the value range notcovered by any of the prior art (conventional) mixers to be establishedin terms of the values for the configuration depending terms (factors)in the mixer gap that may be obtained by using the above proposedequation. According to the present invention, the value range thatcannot be calculated easily by using the prior art index (theory) or isdifficult to be obtained unless it is measured actually can beestablished.

According to the method for manufacturing the foods, pharmaceuticalmedicines or chemical products by subjecting the fluid being processedto the emulsification, dispersion, particle size breakup or mixingprocess that occurs by using the mixer of the rotor-stator type, theparticular mixer running time and the drop diameters thus obtainedduring the particular running time for the fluid being processed can beestimated by calculating the homogenization index using the Equationproposed by the present invention, and the foods, pharmaceuticalmedicines or chemical products having the desired drop diameters canthus be manufactured.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view illustrating a mixer unit that is includedin the mixer of the so-called rotor-stator type;

FIG. 2 illustrates the mixer of the rotor-stator type that runs in theexternal circulation mode (the externally circulated mixer) and themixer of the rotor-stator type that runs in the internal circulationmode (the internally circulated mixer),

FIG. 3 illustrates the mode in which the particle size breakup trend forthe drop diameters can be investigated;

FIG. 4 illustrates the mode in which the experimental results on themixer of the rotor-stator type that runs in the external circulationmode (the externally circulated mixer) can be used to estimate theperformance of the mixer of the rotor-stator type that runs in theinternal circulation mode (the internally circulated mixer);.

FIG. 5 illustrates the relationship (particle size breakup trend)between the processing (mixing) time under the particular runningcondition presented in Table 3 for the mixers A-1 and A-2 in Table 2 andthe resulting drop diameters;:

FIG. 6 illustrates the relationship (particle size breakup trend)between the homogenization index: H.I. and the drop diameters when therotating speed of the rotor for the mixer A-2 in Table 2 is changed.

FIG. 7 illustrates the relationships (drop breakup trend) between thehomogenization index: H.I. and the resulting drop diameter when therotating speed of the rotor for the mixers A-1 and A-2 in Table 2 ischanged;

FIG. 8 illustrates relationship (particle size breakup trend) betweenthe homogenization index: H.I. and the resulting drop diameter when therotating speed of the rotor for the mixers A-2 and B in Table 2 ischanged;

FIG. 9 illustrates the relationship (particle size breakup trend)between the homogenization index: H.I. and the resulting drop diameterwhen the rotating speed of the rotor for the mixers A-1, A-2 and B inTable 2 is changed;

FIG. 10 is a perspective view illustrating one example of the rotor thatis included in the mixer of the rotor-stator type according to thepresent invention.

FIG. 11 is an exploded perspective view illustrating one example of themulti-staged emulsification mechanism that is employed in the mixer ofthe rotor-stator type according to the present invention;

FIG. 12 illustrates the direct injection system that is employed in themixer of the rotor-stator type according to the present invention, inwhich (a) is a plan view and (b) is a side view; and

FIG. 13 illustrates the relationship (particle size breakup trend)between the homogenization index: H.I. and the resulting diameter whenthe nutrition regulated foods that are available on the commercialmarket are mixed together by using the mixer of the rotor-stator type.

BEST MODE OF EMBODYING THE INVENTION

In describing the present invention below, the homogenization index:H.I. which can be derived by calculating the Equation 1 given below andwhich is proposed by the present invention is used to discuss, compareor estimate the particle size breakup effect (particle size breakuptrend) in the mixer of the rotor-stator type.

$\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$

In the Equation 1,

H.I: Homogenization Index [m²/s³]σ: Concentration [kg/m³]σh: Volume of the Gap [m³]

P_(h): Power Consumption [W]

Q: Flow Rate [m³/s]t_(m): Mixing Time [s]V: Fluid being Processed [m³]

N_(p): Number of Powers [-] N_(qd): Number of Flow Rates [-] h: Heightof Stator [m] d: Diameter of Hole of Stator [m]

n_(s): Number of Holes of Stator [-]

l: Thickness of Stator [m]

σ: Gap between Rotor and Stator [m]

N: Number of Rotations [1/s]

C_(n): Configuration Depending Term for Gap [m⁵]

By using the homogenization index: H.I. thus obtained by calculating theEquation 1, it is possible to discuss (compare or estimate) the particlesize breakup effect (particle size breakup trend) in the mixer of therotor-stator type systematically even though there may be anydifferences in the mixer configuration, the stator configuration, themixer's running condition (processing time), the mixer's scale (sizes)and the like.

In the present invention, the mixer's performance can be estimated bymeasuring the magnitude (smallness or greatness) of the values for theconfiguration dependent term: C_(h) [-] in the gap. Those values arespecific to each of the mixers of the various types, and can be obtainedby measuring the components included in the Equation 1 for deriving thehomogenization index: H.I., such as the power requirements and flowrates during the running time and the respective sizes of the rotor andstator.

As it is clear from the Equation 1 proposed by the present invention toallow the value for the homogenization index: H.I. to be derived, thevalue for the configuration dependent term: C_(h)[-] is specific to eachof the mixers of the various types, and may vary depending on the gapbetween the rotor and stator δ[m], the stator's hole diameter d[m], thestator's number of holes n_(s)[-], the stator's thickness l[m], thenumber of flow rates N_(qd)[-], and the number of powers N_(p)[-].

Then, the performance of each of the mixers of the various types can beestimated by comparing (estimating) the magnitude (smallness orgreatness) of the value for the configuration depending term: C_(h)[-]in the gap which is one of the components included in the Equation 1proposed by the present invention for deriving the value for thehomogenization index: H.I.

More specifically, by comparing (estimating) one of the componentsincluded in the Equation 1 of the present invention for deriving thevalue for the homogenization index H.I., that is, the configurationdepending term: C_(h)[-] which is specific to each of the mixers of thevarious types, it is found that the performance of each of the mixers ofthe various types can be estimated and the high performance mixer can bedesigned (developed and fabricated) accordingly.

By matching the values of the homogenization index: H.I. obtained on theexperimental rotor-stator type mixer installation and/or on the pilotplant installation against the values for the homogenization index: H.I.obtained on the actual mixer installation intended for scaling up orscaling down the mixer so that the former H.I. values can conform withthe latter H. I. values, it is also found that the mixer can be scaledup or scaled down.

By calculating the values for the homogenization index: H.I. using theEquation 1 proposed by the present invention for deriving thehomogenization index: H.I. when the foods (such as dairy products,drinks, etc.), pharmaceutical medicines (such as the quasi-drugs) orchemical products (such as the cosmetics) are to be manufactured bysubjecting the fluid being processed to the emulsification, dispersion,particle size breakup, mixing or any other process that occurs by usingthe rotor-stator type mixer, it is also found that those foods,pharmaceutical medicines or chemical products can be manufactured byestimating the mixer running time and the drop diameters obtained duringthe mixer running time for the fluid being processed.

As noted, it has been demonstrated by the embodiment of the presentinvention that the nutritive components (which correspond to thecomponents such as the fluid foods, the powder milks prepared forbabies) which have been manufactured according to the present inventionhave the good taste feeling, physical properties, quality and the like,and are also excellent from the viewpoint of the hygienic care orworkability. Therefore, the present invention should preferably beapplied to the manufacture of the foods or pharmaceutical medicines,more particularly it should be applied to the foods. Much morepreferably, it should be applied to the nutritive components or dairyproducts. The most particularly preferred application of the presentinvention is the nutritive components and dairy products that containthe highly concentrated composition.

Change in the homogenization index: H.I. versus the resulting change inthe drop diameter (particle size breakup trend): A liquid that simulatesa dairy product is prepared so that it can be used in estimating thedrop diameters. This liquid that simulates the dairy product containsthe milk protein concentration (MPC, TMP (total milk protein)), rapeseedoil and water. Its composition and ratio are given in Table 1.

TABLE 1 Composition Ratio of Simulated Liquid for Milk ProductComposition Milk Product Concentrate (MPC) 8.0% Rape Seed Oil 4.5% Water87.5%  Total. 100%  Ratio Protein/Water 9.1% Oil/Protein 56.3% Oil/Water 5.1% Properties Density 1028 kg/m³ Viscosity 15 mPa · s

The mixer performance was estimated on the experimental basis bychecking the particle size breakup trend for the drop diameters. Asshown in FIG. 3, the externally circulated unit was provided, and thedrop diameters were measured on the middle way of the fluid path byusing the laser diffraction-type particle size analyzer (SALD-2000 asoffered by Shimazu Manufacturing Company).

In the present invention, however, it is found that as far as theinternally circulated mixer in particular is concerned, it is difficultto grasp the particle size breakup trend for the drop diameters when theparticle size breakup trend for the drop diameters is reviewed on theexperimental basis and the mixer performance is then estimated. For theinternally circulated mixer and the externally circulated mixer,however, they are common in that either of those mixers comprises themixer unit 4 which includes the stator 2 having the plurality ofopenings (holes) 1 and the stator which is disposed on the inner side ofthe stator 3 and spaced by the particular gap 6 away from the stator 2,as shown in FIG. 1. When the performance of the internally circulatedmixer was then estimated. This was done by using the results obtained byestimating the externally circulated mixer, under the assumption thatthe internally circulated mixer comprised the same mixer unit as theexternally circulated mixer which included the rotor and stator eachhaving the same dimension (size), configuration and structure as theexternally circulated mixer as shown in FIG. 4.

Then, the respective performances of the three different mixers werecompared. The specifications of those mixers which were used for thecomparison are given in Table 2.

TABLE 2 Summary of Mixer Mixer A-1 Mixer A-2 Mixer B 1.5 L 1.5 L 9 LStator No. 6 6 7 Rotor Diameter [mm] D 30 30 57 Maximum Rotation Speed26000 26000 8400 [rpm] N_(max) Maximum Motor Driving 0.9 0.9 1.5 Power[kW] P_(g,) _(max) Number of Openings [—] n_(s) 3 6 5 Gap Size [mm] δ0.15 0.25 0.25 Gap Volume [m³] v_(g) 6.08 × 10⁻⁸ 8.44 × 10⁻⁸ 4.24 × 10⁻⁷Number of Rotor blades

In Table 2, the mixers A-1 and A-2 have the same capacity of 1.5 litersand have the same size although they are offered by the samemanufacturer

In Table 2, it is shown that the gap volume: V_(g) corresponds to thevolume in the gap δ in FIG. 1.

The number of agitating blades for each of the rotors 3 that is includedin each of the mixers A-1 and A-2 (having the capacity of 1.5 liters)and B (having the capacity of 9 liters) is equal to four.

The experimental conditions and the values that were obtained bycalculating the homogenization index for those three different mixersunder those experimental conditions are presented in Table 3.

TABLE 3 Experimental Conditions and Calculated Values Stator No. MixerA-1 Mixer A-2 Mixer B Rotational Speed N [rpm] 17000 17000 8400 1360013600 6720 8400 8400 Rotor Tip Speed u [m/s] 27 27 25 21 21 20 13 13Configuration Dependent 2.57 × 10⁻⁸ 1.46 × 10⁻⁸ 2.50 × 10⁻⁶ Term C_(h)[m⁵] 2.16 × 10⁻⁸ 7.42 × 10⁻⁹ 9.30 × 10⁻⁷ 2.99 × 10⁻⁸ 1.09 × 10⁻⁸Homogenization Index 1.11 × 10⁵  6.28 × 10⁴  1.07 × 10⁵  H.I. [m²/s³]3.80 × 10⁴  1.31 × 10⁴  1.63 × 10⁴  7.66 × 10³  2.78 × 10³ 

From the values of the homogenization index obtained by the Equation 1and presented in Table 3, it was estimated that the particle sizebreakup effect (particle size breakup performance) would become higheras the gap in the mixer is narrower and as the number of rotations forthe stator is greater.

For the mixers A-1 and A-2 in Table 2, the relationship (particle sizebreakup trend) between the processing (mixing) time under the runningconditions and the resulting drop diameters is then presented in FIG. 5.

FIG. 6 presents the relationship (particle size breakup trend) betweenthe homogenization index proposed by the present invention and theresulting drop diameters in the case in which the speed of rotation ofthe rotor for the mixer A-2 in Table 2 was changed.

For the mixers A-1 and A-2 in Table 2, the relationship (particle sizebreakup trend) between the homogenization index: H.I. proposed by thepresent invention and the resulting drop diameters in the case in whichthe speed of rotation of the rotor of each of the mixers is presented inFIG. 7.

For the mixers A-2 and B in Table 2, the relationship (particle sizebreakup trend) between the homogenization index: H.I. proposed by thepresent invention and the resulting drop diameters in the case in whichthe speed of rotation of the rotor of each of the mixers is presented inFIG. 8.

For the mixers A-1, A-2 and B in Table 2, the relationship (particlesize breakup trend) between the homogenization index: H.I. proposed bythe present invention and the resulting drop diameters in the case inwhich the speed of rotation of the rotor of each of the mixers ispresented in FIG. 9.

In Table 3, when the homogenization index: H.I. is calculated andcompared with the results presented in FIG. 5 through FIG. 9, it isfound that the assumed values (theoretical values) and the measuredvalues (actually measured values) exhibit the similar trends and thatthe particle size breakup effect (particle size breakup performance)will become higher as the gap δ of the mixer is smaller for all numbersof the rotation.

When the results obtained by the experiments were organized properlywith the processing (mixing) time being given along the X coordinate, onone hand, it was found that the changes in the drop diameter (particlesize breakup trend) could not be expressed (estimated) comprehensively.

When the results obtained by the experiments were plotted with thehomogenization index being given along the X coordinate, on the otherhand, it was found that the changes in the drop diameter (particle sizebreakup trend) could be expressed (estimated) comprehensively.

As this is mentioned before, it is found that the drop diameter willhave the trend showing that the drop diameter will be decreasing in thesame manner even though there are any differences in the runningconditions (such as the number of rotations and mixing time) and mixer'sconfiguration (such as the gap and the number of openings).

As it is described more specifically, it is clear that thehomogenization index: H.I., which can be obtained by the Equation 1below as proposed by the present invention, can represent the index thatallows the performance for the mixer of the stator-rotor type to beestimated by taking the differences in the mixer running conditions andconfiguration into account.

Furthermore, it was found that the drop diameter will be changing,depending upon the values for the homogenization index: H.I. even thoughthere are any differences in the mixer's scale (size). It was also foundthat the drop diameter would be changing in the same manner regardlessof the difference in the mixer's scale.

It may be apparent from the foregoing description that the mixer of therotor-stator type can be scaled up by matching the mixer against thevalues (sizes) of the homogenization index: H.I. proposed by the presentinvention so that the mixer can conform with those values, and then bytaking the differences in the running condition and configuration intoaccount comprehensively.

For the mixer which depends on the gap and opening, the presentinvention allows the mixer's performance estimation and scale-upoperations to be performed by taking the particle size breakup operationeffect and emulsification effect into account comprehensively. Accordingto the present invention in one of its specific forms, the theory thatis applicable to a wider range of mixers can be implemented anddeveloped on the basis of the performance estimation method and scale-upmethod which have been used.

(Configuration and Design of High Performance Mixer)

In the present invention, the configuration of the high performancemixer can be defined by using the values for the mixer's performanceindex derived from the Equation 1 of the present invention as the indexthat may be used to estimate the mixer's performance, and then by usingthe values for the estimation that results from the above as thereference information. Then, the high performance mixer can be designedfrom this definition. The general structure of the mixer that may thusbe designed is shown in FIGS. 10 through 12.

(Moving Stator)

When the mixer of the rotor-stator type is used to dissolve (mix) thepowdery material or liquid material, and to thereby manufacture theemulsified products, it is possible that the mixer will process thepowdery material while the air that has been introduced with the powderymaterial into the mixer remains not to be separated from the introducedpowdery material. If this situation occurs, the liquid thus mixed maycontain fine air bubbles produced by mixing the powdery material. Forthose years, it has been known that if the mixed liquid is emulsifiedwith such fine air bubbles remaining in the liquid, the particle breakupor emulsification performance (effect) will become worse, as comparedwith the case in which the mixed liquid is emulsified with no airbubbles remaining in the liquid.

In order to prevent such fine air bubbles being produced at the initialstage of dissolving the powdery material, therefore, it is desirablethat the mixer is equipped with a moving stator mechanism. Inparticular, when the powdery material that may tend to produce the airbubbles more easily is processed so as to manufacture the emulsifiedproducts, it is more desirable that the mixer should be equipped withthe moving stator mechanism. By moving the moving stator away from therotor at the initial stage of dissolving the powdery material, thepowdery material can be diffused quickly into the liquid being mixed orprepared. This can be performed without causing any high energydissipation. It is preferred that the dissolving, particle size breakupand emulsifying steps for the powdery material should be performed bymoving the stator closer to the rotor on the production mode.

(Multistage Homogenizer (Multistage Emulsifying Mechanism)

As described above, it is confirmed that the performance (effect) withwhich the particle size breakup or emulsification operation occurs willbecome better as the values of the homogenization index: H.I. derivedfrom the Equation 1 proposed by the present invention become larger.

Then, it is desirable that the mixer includes several mixing portionsformed in the gap between the rotor and the stator.

For example, the particle size breakup operation may occur on thepreliminary mode in the gap between the first-stage rotor and stator,and may then be performed on the production mode in the gap between thesecond-stage rotor and stator.

(Direct Injection (Direct Injection Adding Mechanism))

As it is clear from the mixer performance estimation which serves as theindex for the homogenization index: H.I. derived from the Equation 1proposed by the present invention and from the results obtained byverifying the value for the index, it is confirmed that the particlebreakup or emulsification performance (effect) will become better as thevalue for the above index becomes larger.

Then, by delivering (adding) oils, component in its undissolved state,micro component or other similar components directly into the mixingportions (mixer section), the emulsification or dispersion operation canbe performed more effectively. Particularly, when those components aredelivered (injected) directly into the first-stage stator (the statorlocated radially inwardly), the emulsification or dispersion operationcan be performed much more effectively on the production mode by thesecond-stage stator (the stator located radially outwardly) that followsthe preliminary stage of the first-stage stator.

(Configuration of High Performance Mixer)

As described above, it is confirmed that the particle size breakup oremulsification performance (effect) will become better as the values ofthe homogenization index: H.I. derived from the Equation proposed by thepresent invention are larger. The opening (hole) formed in the statorshould desirably have the round shape instead of the comb-like shape.

Note, however, that there is a risk that the powdery material mightblock the passage through the opening (hole) if the stator has the holediameter of less than 2 mm. In order to permit both the dissolvingprocess and emulsification process for the powdery material to beperformed concurrently, it is desirable that the stator should have thehole diameter of between 2 mm and 4 mm.

In addition, the opening provided in the stator should desirablyrepresent 20% or more of the total opening area on the peripheral wallof the stator.

The shear frequency will become higher as the number of holes providedon the stator (opening area ratio) is increased. The problem is,however, that the strength of the opening on the stator will be affectedin this case. In the prior art, the opening area ratio of between 18%and 36% is generally employed in most cases, but it is desirable thatthe opening area ratio should be equal to 30% or more. It is moredesirable that it should be equal to between 40% and 50%.

In addition, the rotor should desirably be equipped with severalagitating blades extending radially from the center of rotation.Preferably, the rotor should be equipped with six or more agitatingblades, or more preferably eight agitating blades.

Embodiment 1

The following description provides several examples of the preferredembodiment of the present invention by referring to the accompanyingdrawings, but it should be understood that the present invention is notrestricted to those examples of the embodiment described herein and thatvarious modifications or changes may be made without departing from thespirit and scope of the present invention defined in the appendedclaims.

By referring now to FIGS. 10 through 12, the summary of the highperformance mixer will be provided below. The homogenization index: H.I.which is derived from the Equation 1 proposed by the present inventioncan be used as the index for estimating the performance of the highperformance mixer, and the configuration of the high performance mixercan be defined by using the results that are obtained by verifying theestimation for the performance. Then, the high performance mixer can bedesigned by using the definition for the configuration of mixer thusobtained.

The mixer of the rotor-stator type proposed by the present invention maybe characterized by the fact that the mixer comprises the mixer unit 14that includes the plurality of stators each having a plurality ofopenings (holes) and the rotor disposed on the inner side of each of thestators and spaced by the particular gap away from each said stator.Other structural elements are the same as those of the prior art mixerof the rotor-stator type that has been described above. Note that thefollowing description is only directed to one example of the mixer unit14 which has the construction and mechanism that characterize thepresent invention.

The mixer unit 14 for the mixer of the rotor-stator type according tothe present invention includes the rotor 13 and stators 12, 22, each ofwhich is constructed as shown in FIGS. 10 and 11.

Each of the stators 12, 22 is provided with a plurality of round shapeopenings 11 a, 11 b like the stator 2 in the prior art mixer 4 shown inFIG. 1.

Of the stators 12, 22, the stator 22 has the circumferential diameterthat is greater than the stator 12, and is arranged concentrically onthe mixer unit 14 as shown in FIG. 12 (a).

The rotor 13, on the inner side of which the stators 12, 22 are disposedand spaced by the particular gap away from the rotor 13, is equippedwith a plurality of agitating blades extending toward the center ofrotation 17 about which the rotor 13 rotates. In the embodiment shown,for example, the rotor 13 is equipped with eight agitating blades 13 a,13 b, 13 c, 13 d, 13 e, 13 f, 13 g, and 13 h.

Each of the agitating blades 13 a though 13 h has a longitudinal groove15 formed in the radial center thereof and located between the center ofrotation 17 and the outermost end 16. The longitudinal groove 15 has thesame diameter for all agitating blades.

When the mixer unit 14 is formed as shown in 12 (a) and (b), the stator12 may be mounted into the longitudinal groove 15 formed in each of theagitating blade 13 a through 13 h. For each of the agitating blades 13 athough 13 h, then, this creates a gap 2 δ between the wall 16 a of theradial outermost end 16 thereof and the inner peripheral wall 22 a ofthe stator 22. Additionally, a gap is formed between the outermostperipheral face of each of the agitating blades 13 a through 13 h andthe inner peripheral wall 12 a of the stator 12, and a gap is formedbetween the inner peripheral face 15 b of the longitudinal groove 15 ofeach of the agitating blades 13 a through 13 h and the outer peripheralwall 12 b of the stator 12.

As it is apparent for the mixer unit 14 in the mixer of the rotor-statortype that has been described above, the rotor is disposed on the innerside of each of the stators 12, 22 having the different circumferentialdiameter and spaced by the particular gap away from each of the stators.

When the rotor 13 is rotated in the direction of an arrow 20 by causingthe rotary shaft 17 to rotate about its center of rotation, thetwo-stage mixing section including the mixing portion located radiallyinwardly and the mixing portion located radially outwardly is created.This multistage mixing section permits the mixing process to occur withthe high performance.

In the embodiment shown, the mixing portion located radially inwardlymay be created between the outer peripheral surface 15 a of thelongitudinal groove 15 on each of the agitating blades 13 a through 13 hand the inner peripheral wall 12 a of the stator 12 and between theinner peripheral wall 15 of the longitudinal groove 15 on each of theagitating blades 13 a through 13 h and the outer peripheral wall 12 b ofthe stator 12. The mixing portion located radially outwardly may becreated between the wall 16 a of the radially outward end of each of theagitating blades 13 a through 13 h and the inner peripheral wall 22 a ofthe stator 22.

In the mixer of the present invention, each of the stators 12, 22 can bemoving closer to the rotor 13 and moving farther away from the rotor 13in the direction in that the rotary shaft 17 of the rotor 13 extends. Inthe embodiment shown, the rotor 13 can be moving in the direction ofarrows 22, 23 in FIG. 12 in which the rotary shaft 17 extends.

The mixer of the present invention can take the two states as describedearlier, that is, one being the state in which the mixer unit 14 can becreated by allowing the stator 12 to be fitted in the longitudinalgroove formed in each of the agitating blades 13 a through 13 h when therotor 13 is moving in the direction of an arrow 22 in FIG. 12 (b), andthe other being the state in which the rotor 13 is moving away from thestators 12, 13 as shown by the imaginary lines in FIG. 12 (b).

At the initial stage in which the powdery material is dissolved by themixer, it can be dispersed quickly into the mixing liquid by moving therotor 13 away from each of the stators as shown by the arrow 23 in FIG.12 (b). Note that this can be performed without causing the high energydissipation to occur.

The subsequent steps of the dissolution, particle size breakup andemulsification process can be performed efficiently on the productionmode by moving the rotor 13 as shown by the arrow 22 in FIG. 12 (b) sothat the two-stage mixing section can be created in the radially inwarddirection and in the radially outward direction as described above, andthen by moving the rotor 13 in the direction shown by the arrow 20 inFIG. 12 (b).

In the mixer of the present invention, a nozzle 18 extends radiallytoward the center along the upper ends of the stators 12, 22constituting the mixer unit 14 as shown in FIG. 12 (a), allowing thefluid being processed to be delivered directly through the nozzle inlet19 of the nozzle 18 and into the mixing portion (mixer section) as shownby the arrow 21 in FIG. 12.

More specifically, the fluid being processed is delivered as shown bythe arrow 21 into the first-stage mixing section located on the innerside, that is, it is delivered directly through the nozzle inlet 19 andbetween the outer peripheral surface 15 a of each of the longitudinalgrooves 13 a through 13 h and the inner peripheral wall 12 a of thestator 12, where the first-stage mixing (preliminary mixing) occurs.Following the first-stage mixing portion, the fluid being processed isthen delivered into the second-stage mixing portion located on the outerside, that is, between the radially outside end of the wall 16 a of eachof the agitating blades 13 a through 13 h and the inner peripheral wall22 a of the stator 22, where the second-stage mixing occurs on theproductive mode.

It may be appreciated from the above description that the fluid beingprocessed can be delivered directly into the first-stage andsecond-stage mixing portions (mixing section), where it can beemulsified and dispersed more effectively.

Embodiment 2

The test for the particle size breakup operation took place by using thenutrition prepared foods as offered by MIJI NYUGYO CORP. (MEIBALANCE 1.0H.P. (Trademark)).

The compositions and physical properties of MEIBALANCE 1.0 H.P. arepresented in Table 4.

TABLE 4 Nutrition Conditioned Foods (MEIBALANCE HP 1.0 (Trademark)Composition (100 mL) Energy [kcal] 100 Protein [g] 5.0 Fat [g] 2.5Saccharide [g] 14.1 Dietary Fiber [g] 1.2 Ash [g] 0.7 Water [g] 84.3Property Value Osmotic Pressure [mOsm/L] 420 pH (20° C.) [—] 6.7Viscosity (20° C.) [mPa · s] 10 Specific Gravity (20° C.) [—] 1.078

In the current embodiment 2, two types of mixers (one has the capacityof 9 kiloliters and the other has the capacity of 400 liters) were used,and the experiment was conducted by varying the rotating speed of therotor and the accumulating time. Those two types of mixers are the sameas the mixer A which was demonstrated under the embodiment 1 of thepresent invention.

The experimental conditions and the values of the homogenization index:H.I. that were obtained under the experimental conditions are presentedin Table 5.

TABLE 5 Experimental Conditions and Calculated Values (MEIBALACE HP 1.0)H.I.   9 kL 1050 rpm 8.52E+04 1200 rpm 1.43E+05 400 L 1500 rpm 1.71E+052040 rpm 9.76E+05 Time d 50 Accumulated H.I [min] [μm] Time [min][m²/s³] 9 kL 40 1.013 40 3.41E+06 1050 rpm 5 0.771 45 3.84E+06 5 0.74250 4.26E+06 7 0.691 57 4.86E+06 15 0.619 72 6.14E+06 9 kL 7 13.8 71.00E+06 1200 rpm 5 2.37 12 1.72E+06 8 1.2 20 2.86E+06 5 0.925 253.57E+06 5 0.807 30 4.29E+06 5 0.751 35 5.00E+06 5 0.696 40 5.72E+06 100.642 50 7.15E+06 400 L 5.5 5.763 5.5 9.39E+05 1500 rpm 3 2.667 8.51.45E+06 4 1.884 12.5 2.13E+06 10 1.176 22.5 3.84E+06 400 L 5.5 0.68 5.55.37E+06 2020 pm 3 0.617 8.5 8.30E+06 4 0.593 12.5 1.22E+07 10 0.52722.5 2.20E+07

The relationship between the values for the homogenization index: H.I.thus obtained and the drop diameters (the resulting particle sizebreakup trend) is presented in FIG. 3.

When the experimental results were organized into the appropriatetabular forms as the values for the homogenization index: H.I. [m²/s³]proposed by the present invention being given along the X coordinate, itwas found that the change in the drop diameter (the particle sizebreakup trend) can be expressed (estimated) comprehensively andsystematically.

The present invention can be applied to the various industrial fieldssuch as the emulsification, dispersion, particle size breakup and othersimilar processes. Examples of those applications include themanufacturing fields such as foods, pharmaceutical medicines andchemical products since the present invention provides the excellenteffects and functions.

The features of the present invention that have been described so farare summarized below:

(1) For the conventional mixers of the rotor-stator type which areavailable on the commercial market, the performance of those mixers canbe estimated by simply operating the mixers using the usual water (waterrunning) instead of using the actual processing liquid. By reviewing thewater running operation that is convenient for making such review, themost suitable mixer of the rotor-stator type that can meet each user'srequirements for using the mixer can be selected. In this way, the costof selecting the mixer can be reduced, and the time for the review canalso be decreased.(2) By adopting the geometrical size that can maximize the configurationdepending term of the homogenization index: H.I. in the gap, theperformance can be enhanced, designed and manufactured for the inventiveand novel mixers of the rotor-stator type, and the performance for theconventional mixers that already exist can be improved as well.(3) For the various mixers of the rotor-stator type that ranges from thesmall scale to the large scale, the scale-up or scale-down operationsefficiency can be achieved by taking the processing (manufacturing) timerequired for those mixers into consideration.(4) What is required to obtain the particle size effect (drop diameter)that can meet each user's requirements is only to estimate theprocessing (agitating) time required for that purpose and to operatethose mixers with the minimum running (processing) time under suchestimation. In this way, the running time required for such mixers canbe reduced, and the energy requirements can thus be saved.(5) In accordance with the present invention, the mixers of therotor-stator type that provide the higher particle size breakup andemulsification effects and higher quality than the typical highperformance (high shear type) rotor-stator type mixers that have beenoffered in the prior art can be manufactured.(6) According to the present invention, the mixers of the rotor-statortype offered by the present invention can provide the higher particlesize breakup and emulsification effects and higher quality than theequivalent mixers offered by the prior art, and the processing time canthus be reduced.(7) For the various mixers of the rotor-stator type that range from thesmall scale to the large scale, the scale-up or scale-down process canbe achieved by tanking the processing (manufacturing) time required forthose mixer into consideration.

1. A mixer of the stator-rotor type comprising a mixer unit thatincludes a stator having a plurality of openings (holes) and a rotordisposed on the inner side of the stator and spaced by a particular gapaway from the stator, the mixer having the construction that is designedby using the Equation 1 given below in such a manner that a particularmixer running time and a particular drop diameter during the particularmixer running time can be obtained when a fluid being processed issubjected to the emulsification, dispersion, particle size breakup ormixing process and by estimating the particular mixer running time andthe resulting drop diameter by using the Equation 1: $\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$ In the Equation 1, H.I: Homogenization Index [m²/s³] ρ:Concentration [kg/m³] νh: Volume of the Gap [m³] P_(h): PowerConsumption [W] Q: Flow Rate [m³/s] t_(m): Mixing Time [s] V: Fluidbeing Processed [m³] N_(p): Number of Powers [-] N_(qd): Number of FlowRates [-] h: Height of Stator [m] d: Diameter of Hole of Stator [m]n_(s): Number of Holes of Stator [-] l: Thickness of Stator [m]: σ: Gapbetween Rotor and Stator [m] N: Number of Rotations [1/s] C_(n):Configuration Depending Term for Gap [m⁵]
 2. The mixer as defined inclaim 1, wherein the stator and rotor are arranged in such a manner thatthey can be moving closer to each and moving farther away from eachother in the direction in which the rotary shaft of the rotor extends.3. The mixer as defined in claim 1, wherein the mixer includes aplurality of stators each having a different diameter and a rotordisposed on the inner side of each of the stators and spaced by aparticular gap away from said each stator.
 4. The mixer as defined inclaim 1, wherein the fluid being processed is introduced into the gapbetween each of the stators and the rotor disposed on the inner side ofeach of the stators and spaced by a particular gap away from said eachstator.
 5. The mixer as defined in claim 1, wherein the rotor includes aplurality of agitating blades extending radially from the center ofrotation.
 6. A method for estimating the performance of a mixer of therotor-stator type comprising a mixer unit that includes a stator havinga plurality of openings (holes) and a rotor disposed on the inner sideof the stator and spaced by a particular gap away from the stator,wherein the method includes the steps of: using the Equation 1 givenbelow to obtain the values for the homogenization index: H.I., measuringthe components included in the Equation1, such as the respective size ofthe rotor and stator and the power requirements and flow rate during therunning time of the mixer, estimating the magnitude (smallness orgreatness) of the values for the configuration dependent term in the gapthat is specific to the mixer, and estimating the performance of themixer: $\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$ In the Equation 1, H.I: Homogenization Index [m²/s³] ρ:Concentration [kg/m³] νh: Volume of the Gap [m³] P_(h): PowerConsumption [W] Q: Flow Rate [m³/s] t_(m): Mixing Time [s] V: Fluidbeing Processed [m³] N_(p): Number of Powers [-] N_(qd): Number of FlowRates [-] h: Height of Stator [m] d: Diameter of Hole of Stator [m]n_(s): Number of Holes of Stator [-] l: Thickness of Stator [m] σ: Gapbetween Rotor and Stator [m] N: Number of Rotations [1/s] C_(n):Configuration Depending Term for Gap [m⁵]
 7. A method for scaling up orscaling down a mixer of the rotor-stator type comprising a mixer unitthat includes a stator having a plurality of openings (holes) and arotor disposed on the inner side of the stator and spaced by aparticular gap away from the stator, wherein the method includes thesteps of: using the Equation 1 given below to obtain the value for thehomogenization index: H.I. on the experimental mixer installation and/orthe pilot plant mixer installation, matching the thus obtained valuesfor the homogenization index: H.I. against the values for thehomogenization index: H.I. on the actual mixer installation so that theformer H.I. values can conform with the latter H.I. values, and scalingup or scaling down the mixer accordingly: $\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$ In the Equation 1, H.I: Homogenization Index [m²/s³] ρ:Concentration [kg/m³] νh: Volume of the Gap [m³] P_(h): PowerConsumption [W] Q: Flow Rate [m³/s] t_(m): Mixing Time [s] V: Fluidbeing Processed [m³] N_(p): Number of Powers [-] N_(qd): Number of FlowRates H h: Height of Stator [m] d: Diameter of Hole of Stator [m] n_(s):Number of Holes of Stator [-] l: Thickness of Stator [m]: σ: Gap betweenRotor and Stator [m] N: Number of Rotations [1/s] C_(n): ConfigurationDependent Term for Gap [m⁵]
 8. Foods, pharmaceutical medicines orchemical products which are manufactured by subjecting a fluid beingprocessed to the emulsification, dispersion, particle size breakup ormixing process that occurs using the mixer of the stator-rotor typewhich comprises a mixer unit that includes a stator having a pluralityof openings (holes) and a rotor disposed on the inner side of the statorand spaced by a particular gap away from the stator, wherein the foods.pharmaceutical medicines or chemical products are manufactured by usingthe Equation 1 given below, estimating the mixer running time and thedrop diameters thus obtained during the mixer running time for the fluidbeing processed, and subjecting the fluid being processed to theemulsification, dispersion, particle size breakup or mixing process thatoccurs using the mixer: $\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$ In the Equation 1, H.I: Homogenization Index [m²/s³] ρ:Concentration [kg/m³] νh: Volume of the Gap [m³] P_(h): PowerConsumption [W] Q: Flow Rate [m³/s] t_(m): Mixing Time [s] V: Fluidbeing Processed [m³] N_(p): Number of Powers [-] N_(qd): Number of FlowRates [-] h: Height of Stator [m] d: Diameter of Hole of Stator [m]n_(s): Number of Holes of Stator [-] l: Thickness of Stator [m]: σ: Gapbetween Rotor and Stator [m] N: Number of Rotations [1/s] C_(n):Configuration Dependent Term for Gap [m⁵]
 9. A method for manufacturingfoods, pharmaceutical medicines or chemical products by subjecting afluid being processed to the emulsification, dispersion, drop breakup ormixing process using a mixer of the stator-rotor type which comprises amixer unit that includes a stator having a plurality of openings (holes)and a rotor disposed inside the stator and spaced by a particular gapaway from the stator, wherein the method includes the steps of: usingthe Equation 1 given below, and estimating the mixer running time andthe drop diameter thus obtained during the mixer running time for thefluid being processed: $\begin{matrix}\begin{matrix}{{H.I.} = {\frac{P_{h}}{\rho \; v_{h}}\frac{Q}{V}t_{m}}} \\{= {\left( \frac{{N_{qd}\left( {N_{p} - {\pi^{2} \cdot N_{qd}}} \right)}d^{8}}{{\pi \cdot h \cdot {\delta \left( {\delta + d} \right)}} + {\frac{\pi}{4}n_{s}{dl}}} \right)\left( \frac{N^{4} \cdot t_{m}}{V} \right)}} \\{= {C_{h}\left( \frac{N^{4} \cdot t_{m}}{V} \right)}}\end{matrix} & {{the}\mspace{14mu} {Equation}\mspace{14mu} 1}\end{matrix}$ In the Equation 1, H.I: Homogenization Index [m²/s³] ρ:Concentration [kg/m³] νh: Volume of the Gap [m³] P_(h): PowerConsumption [W] Q: Flow Rate [m³/s] t_(m): Mixing Time [s] V: Fluidbeing Processed [m³] N_(p): Number of Powers [-] N_(qd): Number of FlowRates [-] h: Height of Stator [m] d: Diameter of Hole of Stator [m]n_(s): Number of Holes of Stator [-] l: Thickness of Stator [m] σ: Gapbetween Rotor and Stator [m] N: Number of Rotations [1/s] C_(n):Configuration Dependent Term for Gap [m⁵]